Design And Analysis Of Low Short-Circuit Current Dual-Three Phase Permanent Magnet Synchronous Generator

The unmanned armored vehicle can improve the safety distance on the battlefield and increase the survival rate of the operators;besides,it has strong maneuverability,can face the dangerous battlefield environment directly,and can realize multi-scene operation,so it has become the development direction of modern armored vehicles.For electric unmanned armored vehicle,it is required to have multi working condition operation capability and high reliability.This puts forward the reliability and high efficiency demand for the unmanned vehicle power supply system.At present,the PMSMs has advantages of high efficiency and high power density.This paper proposes to use the PMSM generator as the unmanned vehicle generator.But in the design of PMSM,we should pay attention to the electromagnetic performance,but also the improvement of reliability and fault tolerance.This paper first studies the operation and design principle of PMSM under the constraints of rectifier.In order to improve the reliability of generator operation and reduce the EMF harmonic of armature winding,two-phase winding connection is adopted.In order to reduce the short circuit current,a new improvement scheme of stator auxiliary teeth is proposed.The analysis shows that the improved structure not only reduces the coupling degree and short circuit current,but also further suppresses the harmonic content of the winding magnetomotive force teeth.The improved PMSM has the advantages of low short circuit current and low magnetomotive power harmonic.Finally,a 24s20 p dual three-phase winding PMSG is developed.The experiment verified the feasibility of the prototype and laid a solid foundation for the design of high-reliability and low-harmonic PMSG.The main contents of the paper are as follows:1.Firstly,the analysis model and control strategy of PMSG are introduced as the theoretical basis for the follow-up research.According to the technical requirements of vehicle permanent magnet generator,the design method of generator under rectifier constraints is analyzed.At the same time,the formula of inherent voltage regulation rate is derived and the suppression measures are proposed.Finally,the main size parameters of the generator are determined according to the power size equation.2.Analyze the principle of harmonic analysis of winding MMF,and propose a generator scheme with dual three-phase windings connected.The principle of dual three-phase winding connection to suppress harmonics is introduced through formulas,and the advantages of the winding structure are simulated and analyzed.The generator design scheme is determined and the electromagnetic performance and simulation diagram of the scheme are listed.Secondly,a stator auxiliary tooth structure is proposed.The analysis found that the auxiliary tooth structure combined with dual three-phase winding connection further reduces the harmonic content of the winding magnetomotive force.3.Through the analytical calculation of winding inductance,the calculation formulas of phase to phase coupling degree and short circuit current and the suppression measures are derived.In order to reduce short-circuit current and improve fault tolerance,the design method of low short-circuit current permanent magnet synchronous generator is studied.Finally,an improved scheme of stator auxiliary teeth is proposed.The analysis shows that the improved structure not only greatly reduces the phase to phase coupling degree and short circuit current,but also further suppresses the winding magnetomotive force harmonics based on the dual-three phase winding.4.Manufacture an experimental prototype according to the design plan,build an experimental platform,conduct experimental tests on the prototype,compare and analyze experimental data and simulation values,and verify the rationality of the design plan.